Microbial Sanitary Properties of Cup Soft Drinks and Hot Beverages From Automatic Vending Machines in Taiwan

YUEH-JONG CHUNG-WANG, LI-PING KUO, A-YANG LIN, JASON DALANG HONG AND YU-YUN TSAI

National Laboratories of Foods and Drugs, Department of Health , Executive Yuan

ABSTRACT

   Totally 459 specimens of cup-soft drinks and hot beverages were sampled from vending machines at Taipei, Taoyuan, Hsinchu, Miaoli, Taichung, Changhwa, Yunlin, Tainan, Chiayi, Kaohsiung, Pington, Ilan, and Hwalien. The sample pHs were around 2.44-2.97 for carbonated soft drinks orange soda, lemonade soda, sarsaparilla, and cola; 2. 73 for lemon tea; 6. 86 for cocoa; 5. 62 for coffee; and 6. 43 for fruit-milk. The average temperature of hot beverages was around 74. 3 - 76. O℃. Mean total viable count in hot lemon tea was 5.9 colony forming units (CFU)/ml; 14. 1 in cola; 31.6 in hot coffee; 51.3 in sarsaparilla; 53.7 in lemonade soda; 89. 1 in orange soda; 3.2 x 100 in cold coffee; 8. 7 x 100 in both cold cocoa and cold lemon tea; 4. 6x10000 in hot cocoa; 9. 6 x 10000 in fruit-milk. The mean total viable count in specimens taken in the summer was significantly lower than those in the spring and winter (p<O. 05) . The unsatisfactory rate of microbial sanitary conditions for cup soft drinks and hot beverages in total viable count was 15.4% . About 3.2% of soft drinks was contaminated with coliforms with the most probable number of 0. 9 - 24 MPN/ml. The soft drinks contaminated with coliform bacteria included lemonade soda, cola, coffee, cold cocoa, and fruits-milk. Streptococcus uberis, Group D Enterococcus faecalis, Bacillus subtilis, and B. cereus were detected in fruit-milk; Group D E. faecalis, B. subtilis, B. cereus, B. circulans, B. thuringiensis, and B. Licheniformis were in hot cocoa; B. subtilis, B. licheniformis, B. cereus, and Serratiafonticola were in hot coffee. Actinobacter calcoaceticus bio. anitratus was found in cold coffee while Group D E. faecium was in cold cocoa. The bacteria identified from fruit-milk powder, cocoa mix, chocolate mix, and chocolate-cocoa mix on the market included B. cereus, B. licheniformis, B. subtilis, B. epidermidis, B. sphaericus, B. thuringiensis, Staphylococcus aureus, and S. warneri. 

Key words: Drinks vending machines, Total viable counts, Coliform, Microbial flora